The studies contained in this pilot project proposal are designed to accumulate data useful in the development of animal models, and, ultimately, pre-clinical data for future clinical trials by investigating strategies for optimizing gene transfer into the pancreas. Pancreas- directed gene transfer is a potentially useful strategy for the treatment of a number of diseases, including cystic fibrosis, diabetes, cancer, and immunologic modulation of allogeneic and xenogeneic transplants. Two approaches will be used: in vivo gene transfer using adenoviruses, and in vivo gene transfer using retroviruses. Attention will be given to the safe delivery of foreign genetic material into the pancreas, as severe acute pancreatitis is a major concern with any manipulation of the pancreas. The proposed research integrates physiological studies with advances in cellular and molecular biology, an approach that will yield significant new insights for the application of genetic therapy to pancreatic manifestations of cystic fibrosis as well as other human diseases. The hypotheses to be tested include: 1a) Adenoviruses be successfully used to transfer foreign genetic material into cells of the rat pancreas in vivo. 1b) In vivo gene transfer can be done safely, and a major complication, pancreatitis, can be attenuated by pharmacologic prophylaxis prior to virus infusion. 2a) Retroviruses can be used to target specific cell populations of the pancreas in models of in vivo gene transfer; 2b) Peptide growth factors can be used to increase pancreatic cell proliferation and in doing so increase the rate of retroviral transduction. The specific aims which will be used to test the above hypotheses are: 1a) To optimize in vivo gene transfer with adenoviruses containing genes for bacterial beta-galactosidase. 1b) To treat rats with a variety of pharmacologic agents (such as octreotide, a long-acting analog of somatostatin or trasylol, a protease inhibitor) or dietary regimens to prevent or attenuate significant pancreatitis in in vivo gene transfer; 2a) To selectively isolate populations of pancreatic cells (islets, lobules, acinar cells) and transduce them with retroviruses containing the gene for bacterial beta-galactosidase in vitro. ; 2b) To expose pancreatic islets, lobules and acini to TGFalpha, insulin, and glucagon, assessing the proliferative response and rate of gene transfer. A variety of cell and molecular biological techniques will be used in these experiments, including Southern blot analysis, tritiated thymidine autoradiography, histochemical staining, cell and tissue culture, and virus propagation. A number of cores will be necessary for the efficient performance of these experiments, including the Vector Core, the Morphology Core, and the Animal Models Core.